Organic compounds, mixtures, compositions, organic light emitting devices and display devices

Abstract

The application discloses an organic compound, a mixture, a composition, an organic light-emitting device and a display device. A chemical structural formula of the organic compound is shown in general formula (1): (1). The organic compound provided by the application has a low refractive index and can be used as a covering layer material to improve the light-emitting efficiency of the organic light-emitting device.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to an organic compound, mixture, composition, organic light-emitting device, and display apparatus. Background Technology

[0002] Currently, organic light-emitting diodes (OLEDs) typically consist of an anode, a cathode, and an organic functional layer between them. The organic material in the functional layer converts electrical energy into light energy, thus achieving organic electroluminescence. To improve the luminous efficiency and lifespan of OLEDs, the organic functional layer often comprises a multi-layered structure, with each layer containing different organic materials. Specifically, based on functional classification, organic functional layers generally include, but are not limited to, hole injection layers, hole transport layers, light-emitting layers, electron transport layers, and electron injection layers. This has enabled the development of numerous commercial electronic devices, leading to the recognition of the performance of OLEDs.

[0003] When an organic light-emitting diode (OLED) operates, a voltage is applied between the anode and cathode. The anode injects holes into the organic functional layer, and the cathode injects electrons into the organic functional layer. The injected holes and electrons meet to form excitons, which emit light when they radiatively transition back to the ground state. This process enables the OLED to emit light. However, over time and with exposure to different wavelengths of light, the OLED is exposed to high-energy ultraviolet light, which can continuously affect the organic layers. To address this issue, a capping layer with ultraviolet absorption properties is typically used on the OLED. Furthermore, the self-emission and wide viewing angle characteristics of the OLED's emissive layer can lead to deviations at different viewing angles because the refractive indices of the glass substrate, metal electrodes, and various organic materials in the multilayer structure do not match the refractive index of the emission wavelength generated by the emissive layer. Recently, adding a low-refractive-index capping layer above the cathode in combination with a high-refractive-index capping layer for optical optimization has been considered an effective method to improve light extraction efficiency.

[0004] Therefore, in order to achieve more stable and efficient organic electroluminescent devices, it is urgent to develop capping materials that meet the above-mentioned ultraviolet absorption characteristics and low refractive index, so as to avoid aging of organic materials, improve light extraction efficiency, and thus improve device lifespan and luminous efficiency. Summary of the Invention

[0005] This application provides an organic compound, mixture, composition, organic light-emitting device, and display device. The organic compound provided in this application is used as a capping material in an organic light-emitting device, which can significantly improve the light extraction efficiency of the organic light-emitting device.

[0006] In a first aspect, this application provides an organic compound, the chemical structural formula of which is shown in general formula (1): (1); in, Z is selected from -CR5 or nitrogen atom, and multiple Z in general formula (1) are selected from the same or different groups; X1 and X2 are each independently selected from at least one of the following: single bond, double bond, oxygen atom, sulfur atom, -NR6, -CR7R8-; X3 is selected from single bonds, double bonds, oxygen atoms, sulfur atoms, -NR6, -CR7R8-, and -CR9-CR. 10 -、-CR 11 =CR 12 At least one of them; R1, R2, R3, R4 and R5 are each independently selected from at least one of hydrogen, a straight-chain alkyl group having 1 to 16 carbon atoms, a branched alkyl group having 1 to 16 carbon atoms, a straight-chain alkoxy group having 1 to 16 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, an aromatic group having 6 to 30 substituted or unsubstituted cyclic atoms, and a heteroaromatic group having 5 to 30 substituted or unsubstituted cyclic atoms. R6, R7, R8, R9, R 10 R 11 and R 12 Each is independently selected from at least one of hydrogen, methyl, substituted or unsubstituted phenyl; a, b, and c are each independently selected from 0 or 1, and a and b are not both 0 at the same time; m and n are each independently selected from 1, 2, 3, 4 or 5.

[0007] A second aspect of this application provides a mixture comprising at least one organic functional material and at least one organic compound as described above, wherein the organic functional material is selected from at least one of hole injection materials, hole transport materials, electron injection materials, electron transport materials, light-emitting auxiliary materials, hole blocking materials, guest materials, host materials, capping materials, and quantum dot materials.

[0008] A third aspect of this application provides a composition comprising at least one organic solvent and at least one organic compound as described above, or the composition comprising at least one of the organic solvents and a mixture as described above.

[0009] A fourth aspect of this application provides an organic light-emitting device, the organic light-emitting device comprising: First electrode; A light-emitting functional layer is disposed on the first electrode; The second electrode is disposed on the side of the light-emitting functional layer away from the first electrode; and A cover layer is disposed on the side of the second electrode away from the light-emitting functional layer; The material of the covering layer includes at least one organic compound as described above, or the material of the covering layer includes a mixture as described above, or the covering layer is made of a composition as described above.

[0010] A fifth aspect of this application provides a display device comprising the organic light-emitting device described above.

[0011] This application provides an organic compound, mixture, composition, organic light-emitting device, and display device. The organic compound in this application contains amide, aromatic, and heteroaromatic groups, which provide conjugated properties, resulting in a high excited-state energy level without affecting the visible light spectrum. Simultaneously, the rigid amide ring framework structure of the organic compound imparts excellent thermal stability. This organic compound combines low-polarity intrinsic molecular properties, high light transmittance, and high thermal stability, making it a high-performance low-refractive-index capping layer material. When this organic compound is used as a low-refractive-index capping layer in conjunction with a high-refractive-index capping layer in an organic light-emitting device, it can effectively improve light extraction efficiency and significantly enhance current efficiency, facilitating the realization of wide color gamut, low power consumption, and high brightness display products. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of an organic light-emitting device provided in an embodiment of this application.

[0013] 100 - Organic light-emitting device; 110 - Substrate; 120 - First electrode; 130 - Light-emitting functional layer; 131 - Hole injection layer; 132 - Hole transport layer; 133 - Light-emitting auxiliary layer; 134 - Light-emitting layer; 135 - Electron transport layer; 136 - Electron injection layer; 140 - Second electrode; 150 - Capping layer; 151 - First sub-capping layer; 152 - Second sub-capping layer. Detailed Implementation

[0014] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing direction in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. In this application, "optionally," "optionally," and "optional" mean that they are optional, that is, they are selected from either "with" or "without" parallel solutions. If multiple "optional" options appear in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" option is independent. In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0015] In this application, aromatic groups, aromatic families, and aromatic ring systems have the same meaning and can be used interchangeably.

[0016] In this application, heteroaromatic groups, heteroaromatic families, and heteroaromatic ring systems have the same meaning and can be used interchangeably.

[0017] In this application, "substitution" means that the hydrogen atom in the substituent is replaced by the substituent.

[0018] In this application, when the same substituent appears multiple times, it can be independently selected from different groups. If the general formula contains multiple R, then R can be independently selected from different groups.

[0019] In this application, "substituted or unsubstituted" means that the defined group may or may not be substituted. When the defined group is substituted, it should be understood that the defined group can be substituted by one or more substituents R, wherein R is selected from, but is not limited to: deuterium, cyano, isocyano, nitro or halogen, alkyl containing 1-20 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, -NR'R'', silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, halocarbamoyl, etc. Formyl, isocyanate, thiocyanate, isothiocyanate, hydroxyl, trifluoromethyl, and the above groups may be further substituted by substituents acceptable in the art; it is understood that R' and R'' in -NR'R'' are independently selected from, but not limited to: H, deuterium, cyano, isocyano, nitro or halogen, alkyl containing 1-10 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, and heteroaromatic group containing 5-20 ring atoms. Preferably, R is selected from, but not limited to: deuterium, cyano, isocyano, nitro or halogen, alkyl containing 1-10 carbon atoms, heterocyclic group containing 3-10 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, halocarbamoyl, formyl, isocyanate group, thiocyanate group, isothiocyanate group, hydroxyl, trifluoromethyl, and the above groups may also be further substituted with substituents acceptable in the art.

[0020] In this application, "ring atom number" refers to the number of atoms in the ring itself of a structural compound obtained by atomic bonding to form a ring (e.g., monocyclic compound, fused ring compound, cross-linked compound, carbocyclic compound, heterocyclic compound). When the ring is substituted by a substituent, the atoms contained in the substituent are not included in the ring-forming atoms. The same applies to the "ring atom number" described below unless otherwise specified. For example, the benzene ring has 6 ring atoms, the naphthalene ring has 10 ring atoms, and the thiophene group has 5 ring atoms.

[0021] In this application, "aryl or aromatic group" refers to an aromatic hydrocarbon group derived from an aromatic ring compound by removing one hydrogen atom. It can be a monocyclic aryl, a fused-ring aryl, or a polycyclic aryl, and for polycyclic rings, at least one of them is an aromatic ring system. For example, "substituted or unsubstituted aryl having 6 to 40 ring atoms" refers to an aryl containing 6 to 40 ring atoms, preferably a substituted or unsubstituted aryl having 6 to 30 ring atoms, more preferably a substituted or unsubstituted aryl having 6 to 18 ring atoms, and particularly preferably a substituted or unsubstituted aryl having 6 to 14 ring atoms, and optionally further substituted on the aryl group; suitable examples include, but are not limited to: phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluoranyl, triphenylene, pyrene, perylene, tetraphenyl, fluorenyl, dinaphthylphenyl, acenaphthyl and their derivatives. It is understandable that multiple aryl groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms, such as C, N or O atoms), specifically acenaphthene, fluorene, or 9,9'-diarylfluorene, triarylamine, and diaryl ether systems should also be included in the definition of aryl.

[0022] In this application, "heteroaryl or heteroaromatic group" refers to an aryl group in which at least one carbon atom is replaced by a non-carbon atom, which can be an N atom, an O atom, an S atom, etc. For example, "substituted or unsubstituted heteroaryl group having 5 to 40 ring atoms" refers to a heteroaryl group having 5 to 40 ring atoms, preferably a substituted or unsubstituted heteroaryl group having 6 to 30 ring atoms, more preferably a substituted or unsubstituted heteroaryl group having 6 to 18 ring atoms, and particularly preferably a substituted or unsubstituted heteroaryl group having 6 to 14 ring atoms. The heteroaryl group may optionally be further substituted, and suitable examples include, but are not limited to, thiophene, furanyl, pyrrole, imidazolyl, diazolyl, triazolyl, imidazolyl, pyridyl, bipyridyl, and pyrimidine. Triazinyl, acridineyl, pyridazinyl, pyrazinyl, quinolinyl, isoquinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridinylpyrimidinyl, pyridinylpyrazinyl, benzothiopheneyl, benzofuranyl, indolyl, pyrroloimidazolyl, pyrrolopyrrolyl, thienopyrrolyl, thienopyrrolyl, furanolyl, furanolyl, thienofuranyl, benzoisoxazolyl, benzoisothiazolyl, benzoimidazolyl, o-diazonyl, phenanthridineyl, primidyl, quinazolinoneyl, dibenzothiopheneyl, dibenzofuranyl, carbazoleyl and their derivatives.

[0023] In this application, "alkyl" can mean straight-chain, branched, and / or cyclic alkyl. The number of carbon atoms in an alkyl group can be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Phrases containing this term, such as "C 1-9"Alkyl" refers to an alkyl group containing 1 to 9 carbon atoms, and each time it appears, it can independently be C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, or C9 alkyl. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-butyl... Pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3 7-Dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl, 2-hexyldecyl, 2-octyldecyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyldodecyl, 2-hexyldodecyl, 2-octyldodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, 2-ethylhexadecyl, 2-butylhexadecyl, 2-hexylhexadecyl, 2-octylhexadecyl, n-hepta ...

[0024] In this application, "amino group" refers to an amine derivative having the structural feature of the formula -N(X)2, wherein each "X" is independently H, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted heterocyclic group, etc. Non-limiting types of amino groups include -NH2, -N(alkyl)2, -NH(alkyl), -N(cycloalkyl)2, -NH(cycloalkyl), -N(heterocyclic)2, -NH(heterocyclic), -N(aryl)2, -NH(aryl), -N(alkyl)(aryl), -N(alkyl)(heterocyclic), -N(cycloalkyl)(heterocyclic), -N(aryl)(heteroaryl), -N(alkyl)(heteroaryl), etc.

[0025] In this application, unless otherwise defined, hydroxyl refers to -OH, carboxyl refers to -COOH, carbonyl refers to -C(=O)-, amino refers to -NH2, formyl refers to -C(=O)H, haloformyl refers to -C(=O)Z (where Z represents halogen), carbamoyl refers to -C(=O)NH2, isocyanate refers to -NCO, and isothiocyanate refers to -NCS.

[0026] In this application, the term "alkoxy" refers to a group with the structure "-O-alkyl", that is, an alkyl group as defined above that is attached to other groups via an oxygen atom. Suitable examples of phrases containing this term include, but are not limited to: methoxy (-O-CH3 or -OMe), ethoxy (-O-CH2CH3 or -OEt), and tert-butoxy (-OC(CH3)3 or -OtBu).

[0027] In this application, the "connected to the single key" "" indicates a connection or fusion site.

[0028] In this application, when no linking site is specified in the group, it means that any linkable site in the group is selected as the linking site.

[0029] In this application, when no fusion site is specified in the group, it means that any fusionable site in the group is selected as the fusion site, preferably two or more sites in the adjacent position of the group are fusion sites.

[0030] In this application, when the same group contains multiple substituents with the same symbol, the substituents can be the same as or different from each other, for example... The six Rs on the benzene ring can be the same or different from each other.

[0031] In this application, the single bonds connecting the substituents extend through the corresponding ring, indicating that the substituent can be attached to any position on the ring, for example... R is attached to any substituted site on the benzene ring; such as express Can be with A fused ring can be formed at any position on the benzene ring.

[0032] The terms cycloalkyl or cycloalkyl as used in this application have the same meaning and are interchangeable.

[0033] This application provides an organic compound, the chemical structural formula of which is shown in general formula (1): (1); in, Z is selected from -CR5 or nitrogen atom, and multiple Z in general formula (1) can be selected from the same or different groups; X1 and X2 are each independently selected from at least one of the following: single bond, double bond, oxygen atom, sulfur atom, -NR6, -CR7R8-; X3 is selected from single bonds, double bonds, oxygen atoms, sulfur atoms, -NR6, -CR7R8-, and -CR9-CR. 10 -、-CR 11 =CR 12 At least one of them; R1, R2, R3, R4 and R5 are each independently selected from at least one of hydrogen, a straight-chain alkyl group having 1 to 16 carbon atoms, a branched alkyl group having 1 to 16 carbon atoms, a straight-chain alkoxy group having 1 to 16 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, an aromatic group having 6 to 30 substituted or unsubstituted cyclic atoms, and a heteroaromatic group having 5 to 30 substituted or unsubstituted cyclic atoms. R6, R7, R8, R9, R 10 R 11 and R 12 Each is independently selected from at least one of hydrogen, methyl, substituted or unsubstituted phenyl; a, b, and c are each independently selected from 0 or 1, and a and b are not both 0 at the same time; m and n are each independently selected from 1, 2, 3, 4 or 5.

[0034] It is understood that the double bond mentioned above can be a carbon-carbon double bond, but is not limited to this. When X1 and X2 are selected from oxygen or sulfur atoms, c is selected from 0.

[0035] In some embodiments, Z, X1, X2, X3, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 None of them contain fluorine atoms. The organic compounds in this application do not contain fluorine atoms, and the intermolecular forces are relatively weak. Therefore, after film formation, they have stronger adhesion to the electrode or organic film interface and more stable interlayer stacking.

[0036] In some embodiments, X1 and X2 are each independently selected from a single bond or -CR7R8-.

[0037] In some embodiments, X3 is selected from -CR7R8-, -CR9-CR 10 -or-CR 11 =CR 12 -

[0038] In some embodiments, the organic compound is selected from any one of formulas (2-1), (2-2), (2-3), (2-4), and (2-5):

[0039]

[0040] .

[0041] In some embodiments, R1, R2, and R5 are each independently selected from at least one of hydrogen, methyl, isopropyl, tert-butyl, adamantane, substituted or unsubstituted phenyl, biphenyl, 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthalene, 2,2-diphenylpropane, tetraphenylmethane, tetraphenylsilane, 9,9-dimethylfluorene, 9-methyl-9-phenylfluorene, and 9,9-diphenylfluorene, or a combination of the above groups.

[0042] In some embodiments, R3 and R4 are each independently selected from at least one of hydrogen, methyl, methoxy, and phenyl.

[0043] In some embodiments, the organic compound is selected from, but is not limited to, any one of the following compounds:

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[0181] ； In the above-described organic compound structure, hydrogen atoms on any group can be substituted or not substituted. When hydrogen atoms on any group in the above structure are substituted, they can be replaced by one or more substituents R, wherein R is selected from, but is not limited to: deuterium, cyano, isocyano, nitro, halogen, alkyl containing 1-20 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, -NR'R'', silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, etc. The groups include haloformyl, formyl, isocyanate, thiocyanate, isothiocyanate, hydroxyl, and trifluoromethyl, and may be further substituted with substituents acceptable in the art; it is understood that R' and R'' in -NR'R'' are independently selected from, but not limited to: H, deuterium, cyano, isocyano, nitro or halogen, alkyl containing 1-10 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, and heteroaromatic group containing 5-20 ring atoms.

[0182] In some embodiments, the organic compound has a low refractive index, wherein the refractive index of the organic compound for light in the wavelength region of 460 nm to 620 nm is less than 1.60; further, the refractive index of the organic compound for light in the wavelength region of 460 nm to 620 nm is in the range of 1.50 to 1.60.

[0183] In some embodiments, the refractive index of the organic compound for light with a wavelength of 460 nm ranges from 1.50 to 1.60. Further, the refractive index of the organic compound for light with a wavelength of 460 nm ranges from 1.53 to 1.59. For example, the refractive index of the organic compound for light with a wavelength of 460 nm can be 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, or 1.59, but is not limited thereto.

[0184] In some embodiments, the refractive index of the organic compound for light with a wavelength of 620 nm ranges from 1.50 to 1.60. Further, the refractive index of the organic compound for light with a wavelength of 620 nm ranges from 1.52 to 1.56. For example, the refractive index of the organic compound for light with a wavelength of 620 nm can be 1.52, 1.53, 1.54, 1.55, or 1.56, but is not limited thereto.

[0185] The organic compound of this application exhibits a low refractive index decrease and a small slope from blue to red light wavelengths, satisfying the low refractive index value required to ensure a high viewing angle in the visible light region. Due to its low refractive index and organic conjugation properties, this organic compound, when used as a low refractive index capping layer material, not only improves current distribution and enhances luminescence uniformity but also acts as an optical transition and anti-reflection agent, effectively improving the light extraction efficiency of light-emitting devices through the microcavity effect.

[0186] In some embodiments, the organic compound can be used as an organic functional material in the organic functional layer of an organic light-emitting device. The organic functional layer includes, but is not limited to, at least one of: a hole injection layer (HIL), a hole transport layer (HTL), an electron injection layer (EIL), an electron transport layer (ETL), a prime layer, a hole blocking layer (HBL), a capping layer (CPL), and an emissive layer (EML).

[0187] In some embodiments, the organic compound may be applied to the coating layer.

[0188] This application also provides a mixture comprising at least one organic functional material and at least one organic compound as described above, wherein the organic functional material is selected from at least one of hole injection materials, hole transport materials, electron injection materials, electron transport materials, light-emitting auxiliary materials, hole blocking materials, guest materials, host materials, capping materials, and quantum dot materials. For example, various organic functional materials are described in detail in WO2010135519A1, US20090134784A1, and WO2011110277A1. The entire contents of these three patent documents are hereby incorporated herein by reference.

[0189] In some embodiments, the organic compound can be used as a capping material, particularly a low-refractive-index capping material.

[0190] This application also provides a composition comprising at least one organic solvent and at least one organic compound as described above, or the composition comprising at least one of the organic solvents and a mixture as described above.

[0191] In some embodiments, the organic solvent may be any one of aromatic or heteroaromatic compounds, esters, aromatic ketones or aromatic ethers, aliphatic ketones or aliphatic ethers, alicyclic or olefinic compounds, or borate esters or phosphate esters, or a mixture of two or more solvents. Preferably, the organic solvent is selected from aromatic or heteroaromatic solvents.

[0192] In some embodiments, aromatic or heteroaromatic solvents include, but are not limited to: p-diisopropylbenzene, pentamene, tetrahydronaphthalene, cyclohexylbenzene, chloronaphthalene, 1,4-dimethylnaphthalene, 3-isopropylbiphenyl, p-methylisopropylbenzene, dipentene, tripentene, pentamethylenetetramine, o-diethylbenzene, m-diethylbenzene, p-diethylbenzene, 1,2,3,4-tetramethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, butanediol, dodecylbenzene, dihexylbenzene, dibutylbenzene, p-diisopropylbenzene, cyclohexylbenzene, benzylbutylbenzene, dimethylnaphthalene, 3-Isopropylbiphenyl, p-methylisopropylbenzene, 1-methylnaphthalene, 1,2,4-trichlorobenzene, 4,4-difluorodiphenylmethane, 1,2-dimethoxy-4-(1-propenyl)benzene, diphenylmethane, 2-phenylpyridine, 3-phenylpyridine, N-methyldiphenylamine, 4-isopropylbiphenyl, α,α-dichlorodiphenylmethane, 4-(3-phenylpropyl)pyridine, benzyl benzoate, 1,1-bis(3,4-dimethylphenyl)ethane, 2-isopropylnaphthalene, quinoline, isoquinoline, methyl 2-furanoate, ethyl 2-furanoate, etc.

[0193] In some embodiments, the aromatic ketone-based solvents include, but are not limited to: 1-tetrahydronaphthone, 2-tetrahydronaphthone, 2-(phenylepoxy)tetrahydronaphthone, 6-(methoxy)tetrahydronaphthone, acetophenone, phenylacetone, benzophenone, and their derivatives, such as 4-methylacetophenone, 3-methylacetophenone, 2-methylacetophenone, 4-methylphenylacetone, 3-methylphenylacetone, 2-methylphenylacetone, etc.

[0194] In some embodiments, the aromatic ether-based solvents include, but are not limited to: 3-phenoxytoluene, butoxybenzene, p-anisaldehyde dimethyl acetal, tetrahydro-2-phenoxy-2H-pyran, 1,2-dimethoxy-4-(1-propenyl)benzene, 1,4-benzodioxane, 1,3-dipropylbenzene, 2,5-dimethoxytoluene, 4-ethylbenzene, 1,3-dipropoxybenzene, 1,2,4-trimethoxybenzene, 4-(1-propenyl)-1,2-dimethoxybenzene, 1,3-dimethoxybenzene, glycidylphenyl ether, dibenzyl ether, 4-tert-butylanisole, trans-p-propenylanisole, 1,2-dimethoxybenzene, 1-methoxynaphthalene, diphenyl ether, 2-phenoxymethyl ether, 2-phenoxytetrahydrofuran, ethyl-2-naphthyl ether, etc.

[0195] In some embodiments, solvents based on aliphatic ketones or aliphatic ethers include, but are not limited to: 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone, 2,5-hexanedione, 2,6,8-trimethyl-4-nonanone, frankinc, forlone, isophorone, di-n-pentyl ketone, pentanyl ether, hexane ether, dioctyl ether, ethylene glycol dibutyl ether, diethylene glycol diethyl ether, diethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol ethyl methyl ether, triethylene glycol butyl methyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, etc.

[0196] In some embodiments, the solvent based on borate esters or phosphate esters includes, but is not limited to: alkyl octanoate, alkyl sebacate, alkyl stearate, alkyl benzoate, alkyl phenylacetate, alkyl cinnamate, alkyl oxalate, alkyl maleate, alkyl lactone, alkyl oleate, etc. Particularly preferred are octyl octanoate, diethyl sebacate, diallyl phthalate, and isononyl isononanoate.

[0197] In some embodiments, the composition further includes an auxiliary solvent, which includes, but is not limited to, at least one of: methanol, ethanol, 2-methoxyethanol, dichloromethane, trichloromethane, chlorobenzene, o-dichlorobenzene, tetrahydrofuran, anisole, morpholine, toluene, o-xylene, m-xylene, p-xylene, 1,4-dioxane, acetone, methyl ethyl ketone, 1,2-dichloroethane, 3-phenoxytoluene, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, ethyl acetate, butyl acetate, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, tetrahydronaphthalene, naphthane, and indene.

[0198] In some embodiments, the Hansen solubility parameter of the organic solvent is within the following range: δd (dispersion force) is in the range of 17.0~23.2 MPa. 1 / 2 The preferred range is 18.5~21.0 MPa. 1 / 2 Scope; δp (polar force) is in the range of 0.2~12.5 MPa. 1 / 2 The preferred range is 2.0~6.0 MPa. 1 / 2 Scope; δh (hydrogen bond strength) ranges from 0.9 to 14.2 MPa. 1 / 2 The preferred range is 2.0~6.0 MPa. 1 / 2 The range.

[0199] In some embodiments, the boiling point of the organic solvent should be considered when selecting it. The boiling point of the organic solvent is greater than or equal to 150°C; preferably greater than or equal to 180°C; more preferably greater than or equal to 200°C; even more preferably greater than or equal to 250°C; further preferably greater than or equal to 275°C; and most preferably greater than or equal to 300°C. When the boiling point of the organic solvent is within the above range, it is beneficial to prevent nozzle clogging of the inkjet printhead.

[0200] It should be noted that the organic solvent can evaporate from the solvent system to form a thin film containing organic functional materials.

[0201] In some embodiments, the composition may be a solution.

[0202] In some embodiments, the composition may also be a suspension.

[0203] In some embodiments, the organic compound or mixture in the composition has a mass percentage of 0.01 wt% to 20 wt%. Preferably, the organic compound or mixture in the composition has a mass percentage of 0.1 wt% to 15 wt%. More preferably, the organic compound or mixture in the composition has a mass percentage of 0.2 wt% to 10 wt%.

[0204] In some embodiments, the composition can be used as a coating or printing ink to prepare organic light-emitting devices, for example, by printing or coating methods.

[0205] The printing or coating methods include, but are not limited to: inkjet printing, nozzle printing, letterpress printing, screen printing, dip coating, spin coating, knife coating, roller printing, torsional roller printing, offset printing, flexographic printing, rotary printing, spraying, brushing or pad printing, slot extrusion coating, etc. Gravure printing, inkjet printing, and other similar methods are preferred.

[0206] Furthermore, the composition may also include one or more other components, such as surfactants, lubricants, wetting agents, dispersants, hydrophobic agents, adhesives, etc., to adjust viscosity, film-forming properties, and improve adhesion, etc., to meet the requirements of relevant printing technologies for the solutions, such as solvent, concentration, viscosity, etc.

[0207] This application also provides an organic light-emitting device 100, please refer to... Figure 1The organic light-emitting device 100 includes a first electrode 120, a light-emitting functional layer 130, a second electrode 140, and a capping layer 150. The light-emitting functional layer 130 is disposed on the first electrode 120; the second electrode 140 is disposed on the side of the light-emitting functional layer 130 away from the first electrode 120; the capping layer 150 is disposed on the side of the second electrode 140 away from the light-emitting functional layer 130; wherein, the material of the capping layer 150 includes at least one organic compound as described above, or the material of the capping layer 150 includes a mixture as described above, or the capping layer 150 is made of a composition as described above.

[0208] In some embodiments, the organic light-emitting device 100 further includes a substrate 110 disposed on the side of the first electrode 120 away from the light-emitting functional layer 130. The substrate 110 can be an opaque substrate or a transparent substrate. When the substrate 110 is a transparent substrate, it can be used to manufacture a transparent organic light-emitting device 100, as seen in Bulovic et al., Nature 1996, 380, p29, and Gu et al., Appl. Phys. Lett. 1996, 68, p2606. The substrate 110 can be a rigid substrate or a flexible substrate with elasticity. The material of the substrate 110 can be, but is not limited to, plastic, metal, semiconductor wafer, or glass. Preferably, the substrate 110 includes at least one smooth surface. More preferably, it is a substrate without surface defects. Preferably, the substrate 110 is flexible, and its material is a polymer film or plastic, including but not limited to polyethylene terephthalate (PET) and polyethylene glycol (2,6-naphthalene) (PEN). The glass transition temperature Tg of the substrate 110 material is greater than or equal to 150°C, preferably greater than or equal to 200°C, more preferably greater than or equal to 250°C, and most preferably greater than or equal to 300°C.

[0209] In some embodiments, one of the first electrode 120 and the second electrode 140 is an anode and the other is a cathode.

[0210] The anode is the electrode for injecting holes, and it can inject holes into the organic functional layer, such as the hole injection layer 131, the hole transport layer 132, or the light-emitting layer 134. The anode may include at least one of a conductive metal, a conductive metal oxide, or a conductive polymer. Preferably, the absolute value of the difference between the work function of the anode and the highest occupied molecular orbital (HOMO) level or valence band level of the light-emitting material in the light-emitting layer 134, or the p-type semiconductor material in the hole injection layer 131, hole transport layer 132, or electron blocking layer, is less than 0.5 eV, preferably less than 0.3 eV, and more preferably less than 0.2 eV. The anode material includes, but is not limited to, at least one of Al, Cu, Au, Ag, Mg, Fe, Co, Ni, Mn, Pd, Pt, indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), or other suitable and known anode materials, which can be readily selected and used by those skilled in the art. The anode material can be deposited using any suitable technique, such as suitable physical vapor deposition methods, including radio frequency magnetron sputtering, vacuum thermal evaporation, electron beam (e-beam), etc. In some embodiments, the anode can be patterned, for example, patterned ITO conductive substrates are commercially available and can be used to fabricate the organic light-emitting device 100 of this application.

[0211] The cathode is the electrode for injecting electrons, and it can inject electrons into organic functional layers, such as electron injection layer 136, electron transport layer 135, or light-emitting layer 134. The cathode may include at least one of a conductive metal or a conductive metal oxide. Preferably, the absolute value of the difference between the work function of the cathode and the lowest unoccupied molecular orbital (LUMO) level or conduction band level of the light-emitting material in the light-emitting layer 134, or the n-type semiconductor material serving as the electron injection layer 136, electron transport layer 135, or hole blocking layer, is less than 0.5 eV, preferably less than 0.3 eV, and more preferably less than 0.2 eV. All materials suitable for use as the cathode of the organic light-emitting device 100 may be used as the cathode material for the device of this application. Cathode materials include, but are not limited to, at least one of Al, Au, Ag, Ca, Ba, Mg, LiF / Al, MgAg alloy, BaF2 / Al, Cu, Fe, Co, Ni, Mn, Pd, Pt, and ITO. The cathode material can be deposited using any suitable technique, such as appropriate physical vapor deposition methods, including radio frequency magnetron sputtering, vacuum thermal evaporation, electron beam (e-beam), etc.

[0212] In this application, the light-emitting functional layer 130 may include one or more film layers, and the light-emitting functional layer 130 includes at least the light-emitting layer 134.

[0213] In some embodiments, the light-emitting functional layer 130 includes a light-emitting layer 134. Correspondingly, the organic light-emitting device 100 includes a first electrode 120, a light-emitting layer 134, a second electrode 140, and a capping layer 150 stacked sequentially.

[0214] In some embodiments, when the light-emitting functional layer 130 comprises multiple film layers, in addition to the light-emitting layer 134, the light-emitting functional layer 130 may also include at least one of the following: a hole injection layer 131, a hole transport layer 132, a light-emitting auxiliary layer 133, an electron blocking layer, a hole blocking layer, an electron transport layer 135, and an electron injection layer 136. Taking the first electrode 120 as the anode and the second electrode 140 as the cathode as an example, a hole transport region is formed between the first electrode 120 and the light-emitting layer 134, and an electron transport region is formed between the second electrode 140 and the light-emitting layer 134; wherein, the space between the first electrode 120 and the light-emitting layer 134 may include at least one of the following: a hole injection layer 131, a hole transport layer 132, a light-emitting auxiliary layer 133, and an electron blocking layer, and the space between the second electrode 140 and the light-emitting layer 134 may include at least one of the following: a hole blocking layer, an electron transport layer 135, and an electron injection layer 136.

[0215] For details, please refer to Figure 1 The light-emitting functional layer 130 includes a hole injection layer 131, a hole transport layer 132, a light-emitting auxiliary layer 133, a light-emitting layer 134, an electron transport layer 135, and an electron injection layer 136. Specifically, the hole injection layer 131 is located on the side of the first electrode 120 (anode) away from the substrate 110; the hole transport layer 132 is located on the side of the hole injection layer 131 away from the first electrode 120; the light-emitting auxiliary layer 133 is located on the side of the hole transport layer 132 away from the hole injection layer 131; the light-emitting layer 134 is located on the side of the light-emitting auxiliary layer 133 away from the hole transport layer 132; the electron transport layer 135 is located on the side of the light-emitting layer 134 away from the light-emitting auxiliary layer 133; and the electron injection layer 136 is located between the electron transport layer 135 and the second electrode 140 (cathode).

[0216] In some embodiments, please refer to Figure 1 The cover layer 150 includes a first sub-cover layer 151 and a second sub-cover layer 152, wherein the second sub-cover layer 152 is located on the side of the first sub-cover layer 151 away from the second electrode 140; wherein the material of the first sub-cover layer 151 includes at least one organic compound as described above, and the refractive index of the first sub-cover layer 151 is less than the refractive index of the second sub-cover layer 152.

[0217] In this embodiment, the capping layer 150 is a double capping layer structure composed of a first sub-capping layer 151 with a low refractive index and a second sub-capping layer 152 with a high refractive index. For the dual-capping layer structure, after the photons emitted by the emitting layer 134 penetrate the metal cathode, they first pass through the low-refractive-index first sub-capping layer 151 to suppress plasmon coupling loss on the metal surface and release photons bound by the metal. The low-refractive-index first sub-capping layer 151 and the high-refractive-index second sub-capping layer 152 form a multi-level optical interface. The total internal reflection critical angle is widened by a stepped refractive index gradient, reducing the total internal reflection loss of the waveguide mode caused by the sudden change in the interface refractive index. At the same time, a secondary microcavity structure is constructed to recover the waveguide mode bound light and generate constructive interference to enhance the optical field. The dual high and low refractive index films work together to achieve broadband destructive interference anti-reflection, reduce Fresnel reflection loss at the interface between the top layer and the air, and improve light transmittance. The synergistic effect of the above multiple optical mechanisms can significantly reduce various types of optical losses inside the device, resulting in a significant improvement in the overall light extraction efficiency of the device. At the same time, the combined effect of the microcavity effect and interference selection effectively narrows the half-width at half-maximum of the emission spectrum, makes the color coordinates closer to the standard value, and effectively reduces the degree of color shift with changing viewing angle, thereby significantly improving color purity and display uniformity.

[0218] The first sub-coating layer 151 is formed by using an organic compound represented by general formula (1), which enables the first sub-coating to obtain a lower refractive index. When combined with the second sub-coating layer 152 with a high refractive index, it can significantly improve the overall light extraction efficiency of the coating layer 150.

[0219] In some embodiments, the first sub-capping layer 151 has a low refractive index, and the refractive index of the first sub-capping layer 151 for light in the wavelength region of 460 nm to 620 nm is less than 1.60; further, the refractive index of the first sub-capping layer 151 for light in the wavelength region of 460 nm to 620 nm is in the range of 1.50 to 1.60.

[0220] In some embodiments, the refractive index of the first sub-capping layer 151 for light with a wavelength of 460 nm ranges from 1.50 to 1.60. Further, the refractive index of the first sub-capping layer 151 for light with a wavelength of 460 nm ranges from 1.53 to 1.59. For example, the refractive index of the first sub-capping layer 151 for light with a wavelength of 460 nm can be 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, or 1.59, but is not limited thereto.

[0221] In some embodiments, the refractive index of the first sub-capping layer 151 for light with a wavelength of 620 nm ranges from 1.50 to 1.60. Further, the refractive index of the first sub-capping layer 151 for light with a wavelength of 620 nm ranges from 1.52 to 1.56. For example, the refractive index of the first sub-capping layer 151 for light with a wavelength of 620 nm can be 1.52, 1.53, 1.54, 1.55, or 1.56, but is not limited thereto.

[0222] In some embodiments, the second sub-capping layer 152 has a high refractive index, and the refractive index of the second sub-capping layer 152 for light in the wavelength region of 460 nm to 620 nm is greater than 1.90. Further, the refractive index of the second sub-capping layer 152 for light with a wavelength of 460 nm is greater than 2.00, and the refractive index of the second sub-capping layer 152 for light with a wavelength of 620 nm is greater than 1.90.

[0223] In some embodiments, the difference between the refractive index of the first sub-coating layer 151 and the refractive index of the second sub-coating layer 152 for light with a wavelength of 460 nm can be greater than or equal to 0.3, preferably greater than or equal to 0.4, and more preferably greater than or equal to 0.5, so as to reduce total internal reflection of light at the interface and improve light extraction efficiency.

[0224] In some embodiments, the difference between the refractive index of the first sub-coating layer 151 and the refractive index of the second sub-coating layer 152 for light with a wavelength of 620 nm can be greater than or equal to 0.3, preferably greater than or equal to 0.4, and more preferably greater than or equal to 0.5, so as to reduce total internal reflection of light at the interface and improve light extraction efficiency.

[0225] In some embodiments, the peak wavelength range of the emission spectrum of the organic light-emitting device 100 is 300 nm to 1000 nm; preferably, the peak wavelength range is 350 nm to 900 nm; more preferably, the peak wavelength range is 400 nm to 800 nm.

[0226] In some embodiments, the organic light-emitting device 100 may be, but is not limited to, organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPVs), organic light-emitting electrochemical cells (OLEECs), organic field-effect transistors (OFETs), organic light-emitting field-effect transistors (OLEFETs), organic lasers, organic spintronic devices, organic sensors, and organic plasmon emitting diodes (OLEFETs). Preferably, it is an organic light-emitting diode, an organic light-emitting cell, or an organic light-emitting field-effect transistor.

[0227] In some embodiments, the organic light-emitting device 100 can be applied to a variety of electronic devices, such as display devices, lighting devices, light sources, sensors, etc.

[0228] This application also provides a display device, which includes the organic light-emitting device 100 as described above. This display device can be used in fields such as smartphones, tablets, smart wearable devices, televisions, virtual reality (VR), microdisplays, and automotive displays, but is not limited thereto.

[0229] The present application will now be described in conjunction with preferred embodiments, but the present application is not limited to the following embodiments. It should be understood that those skilled in the art, guided by the concept of the present application, should realize that any changes made to the various embodiments of the present application will be covered by the spirit and scope of the claims of the present application.

[0230] The organic compounds and their preparation methods of this application are further described in detail below with reference to specific embodiments. Unless otherwise specified, all raw materials used in the following embodiments are commercially available products.

[0231] (1) Synthesis of organic compounds: Example 1 The synthetic route for compound P-1 is as follows:

[0232] Reactant A (0.1 mol) and reactant B (0.2 mol) were weighed and placed in a clean three-necked flask, dissolved in acetic acid, and purged with nitrogen three times. The mixture was then refluxed at 100°C for 12 h under a nitrogen atmosphere. After natural cooling, the mixture was washed with water and separated. The organic phase was dried and then evaporated to dryness. Column chromatography was used to obtain compound P-1 with a yield of 90%. The atmospheric pressure solid probe (ASAP) mass spectrometry results for compound P-1 were: m / z [H + The elemental composition was 667. The theoretical values ​​of elemental analysis by inductively coupled plasma (ICP) were C, 79.25; H, 6.95; N, 4.20; O, 9.60, while the measured values ​​were C, 79.2; H, 7.0; N, 4.2; O, 9.6. This proves that the obtained product is compound P-1.

[0233] Examples 2-20 Following the preparation method of compound P-1 in Example 1, compounds P-2 to P-20 in Table 1 were prepared using the reactants shown in Table 1. In Table 1, "Serial Number" indicates the synthesis example number.

[0234] Table 1. Information on reactants and products in Examples 1-20

[0235] Comparative Example This application also provides Comparative Examples 1-4, the organic compounds in Comparative Examples 1-4 are designated as "REF01-REF04", and their chemical structural formulas are shown below:

[0236] (2) Refractive index test: The compound of this application was deposited onto single-crystal silicon by vacuum evaporation to form a 50 nm thick film. The single-crystal silicon was then placed on an ellipsometer sample stage with an incident angle of 70° and tested under atmospheric conditions. The refractive index (n) of the compound was obtained by fitting the ellipsometer data. The results are shown in Table 2.

[0237] Table 2 Refractive Index of Compounds

[0238] As shown in Table 2, the refractive indices of compounds P-1 to P-20 in the embodiments of this application are all below 1.60 in the 460 nm to 620 nm region, and are lower than the refractive indices of comparative compounds REF01 to REF04. The refractive index decreases slowly and has a small slope from blue to red light, which meets the low refractive index value required to ensure a high viewing angle in the visible light region. Due to their low refractive index and organic conjugation properties, when used as the first sub-capping layer material, the compounds of this application can not only improve current distribution and enhance luminous uniformity, but also act as optical transition and anti-reflection agents, effectively improving the light extraction efficiency of the light-emitting device through the microcavity effect. Furthermore, the refractive index differences across multiple layers can broaden the critical angle for total internal reflection, thereby effectively improving color shift when applying multi-angle display devices.

[0239] (3) Fabrication and characterization of OLED devices by Figure 1 Taking the OLED device fabrication shown as an example, the following detailed description of the fabrication method of OLED devices using the compounds of this application will be provided through specific device embodiments.

[0240] In the following method for fabricating OLED devices, ITO conductive glass is used as the anode substrate (including substrate 110 and first electrode 120 (anode)), HATCN is used as the hole injection material, HT as the hole transport material, Prime as the light-emitting auxiliary material, BH as the host material of the light-emitting layer 134, BD as the dopant material of the light-emitting layer 134, ET and lithium 8-hydroxyquinoline (Liq) as electron transport materials, Liq as the electron injection material, and Al as the cathode material. Furthermore, the series of organic compounds from the aforementioned synthesis examples 1-20 are used as materials for the first sub-capping layer 151, and CPL01 is used as the material for the second sub-capping layer 152 to fabricate corresponding OLED devices. The chemical structural formulas of HATCN, BH, BD, HT, Prime, ET, and Liq are shown below:

[0241] The following specific examples illustrate the fabrication process of OLED devices using the above-mentioned materials.

[0242] Taking the fabrication method of OLED devices using compound P-1 as the first sub-capping layer 151 material as an example, the resulting OLED device is denoted as "OLED-1 device". The fabrication method of OLED-1 device includes the following steps: Step a: Cleaning of the ITO conductive glass substrate (including substrate 110 and first electrode 120 (anode)). An ITO conductive glass substrate is provided, and the substrate is ultrasonically cleaned using one or more cleaning agents such as deionized water, acetone, isopropanol, or chloroform to improve the power function of the anode.

[0243] Step b: Forming a hole injection layer 131 on the anode. Hole injection material HATCN is deposited on the anode at a deposition rate of 1 Å / s to obtain a hole injection layer 131 with a thickness of 30 nm.

[0244] Step c: Form a hole transport layer 132 on the hole injection layer 131. Hole transport material HT is deposited on the hole injection layer 131 at a deposition rate of 1 Å / s to obtain a hole transport layer 132 with a thickness of 60 nm.

[0245] Step d: A light-emitting auxiliary layer 133 is formed on the hole transport layer 132. A light-emitting auxiliary material Prime is deposited on the hole transport layer 132 at a deposition rate of 1 Å / s to obtain a light-emitting auxiliary layer 133 with a thickness of 10 nm.

[0246] Step e: Forming a light-emitting layer 134 on the light-emitting auxiliary layer 133. Using BH as the host material and BD as the dopant material, with a mass ratio of BH to BD of 98:2, BH and BD are deposited on the light-emitting auxiliary layer 133 at a deposition rate of 1 Å / s to obtain a light-emitting layer 134 with a thickness of 25 nm.

[0247] Step f: Form an electron transport layer 135 on the luminescent layer 134. In a vacuum chamber, electron transport materials ET and Liq are placed in different evaporation crucibles and subjected to high vacuum (1×10⁻⁶) conditions. -6 Under millibars, ET and Liq were co-deposited at a weight ratio of 5:5 to form an electron transport layer 135 with a thickness of 30 nm on the luminescent layer 134.

[0248] Step g: Form an electron injection layer 136 on the electron transport layer 135. Electron injection material Liq is deposited on the electron transport layer 135 at a deposition rate of 1 Å / s to obtain an electron injection layer 136 with a thickness of 1 nm.

[0249] Step h: A second electrode 140 (cathode) is formed on the electron injection layer 136. The cathode material Al is deposited on the electron injection layer 136 at a deposition rate of 1 Å / s to obtain a cathode with a thickness of 100 nm.

[0250] Step i: Form a capping layer 150 on the cathode. First sub-capping layer 151 material compound P-1 and second sub-capping layer 152 material CPL01 are sequentially deposited on the cathode at a deposition rate of 1 Å / s to obtain first sub-capping layer 151 and second sub-capping layer 152 with thicknesses of 20 nm and 60 nm, respectively. First sub-capping layer 151 and second sub-capping layer 152 together constitute capping layer 150.

[0251] Step j: The device obtained by layer-by-layer deposition is placed in a nitrogen atmosphere glove box and encapsulated with ultraviolet curing resin to finally obtain the OLED device.

[0252] In this embodiment, the structure of the prepared OLED-1 device is: ITO / HATCN (30 nm) / HT (60 nm) / Prime (10 nm) / BH:BD (2%, 25 nm) / ET:Liq (5:5, 30 nm) / Liq (1 nm) / Al (100 nm) / compound P-1 (20 nm) / CPL01 (60 nm).

[0253] Fabrication of OLED-2 to OLED-20 devices: Referring to the fabrication method of OLED-1, the compounds synthesized in Examples 2 to 20 were used as materials for the first sub-capping layer 151 of the OLED devices, respectively, to prepare OLED-2 to OLED-20 devices. It can be understood that in the above-mentioned fabrication methods of OLED-1 to OLED-20 devices, except for the materials used in the first sub-capping layer 151, all other experimental conditions are the same.

[0254] Comparison of devices OLED-R1 to OLED-R6: The comparative devices OLED-R1 and OLED-R2 are similar in structure and fabrication method to OLED-1, except that they do not use a double-layer capping material, but only a single-layer capping layer. All other experimental conditions are the same. Specifically, the structure of the comparative device OLED-R1 is: ITO / HATCN (30 nm) / HT (60 nm) / Prime (10 nm) / BH:BD (2%, 25 nm) / ET:Liq (5:5, 30 nm) / Liq (1 nm) / Al (100 nm) / CPL01 (60 nm). The structure of the comparative device OLED-R2 is: ITO / HATCN (30 nm) / HT (60 nm) / Prime (10 nm) / BH:BD (2%, 25 nm) / ET:Liq (5:5, 30 nm) / Liq (1 nm) / Al (100 nm) / compound P-1 of this application (60 nm).

[0255] Comparative devices OLED-R3 to OLED-R6 were prepared using the same fabrication method as OLED-1, with comparative compounds REF01 to REF04 used as the first sub-capping layer 151 materials. It is understood that, apart from the different materials used in the first sub-capping layer 151, all other experimental conditions were identical in the fabrication methods of comparative devices OLED-R3 to OLED-R6.

[0256] The current-voltage (JV) characteristics of devices OLED-1 to OLED-20 and OLED-R1 to OLED-R6 were characterized, and important parameters such as BI value (BI = current efficiency / CIEy, unit cd / A / CIEy, is the industry standard performance index of blue OLED devices) were recorded, as shown in Table 3.

[0257] Table 3 BI values ​​of organic light-emitting devices

[0258] The data in Table 3 show that, compared with the comparative device OLED-R1 which only has a high refractive index capping layer, the device using compounds P-1 to P-20 of this application as a dual capping layer with a low refractive index first sub-capping layer 151 and a high refractive index second sub-capping layer 152 has a BI value that is 19% to 35%.

[0259] Compared to the OLED-R2, a comparative device with only a low-refractive-index capping layer, the device using compounds P-1 to P-20 of this application as a dual-layer capping layer with a low-refractive-index first sub-capping layer 151 and a high-refractive-index second sub-capping layer 152 has a BI value that is 42% to 57%.

[0260] Compared with OLED-R3 to OLED-R6, which use dual-layer capping devices with comparative compounds REF01 to REF04, the devices using compounds P-1 to P-20 of this application as a low-refractive-index first sub-capping layer 151 and a high-refractive-index second sub-capping layer 152 have a BI value that is increased by 24% to 54%.

[0261] The BI value corresponds to the ratio of device current efficiency to chromaticity value. A higher BI value indicates that the organic light-emitting device 100 exhibits higher blue light purity (lower y chromaticity) at the same current efficiency, or better luminous efficiency at the same color purity. Therefore, devices using the compound of this application as a dual-layer capping layer (low refractive index first sub-capping layer 151 paired with high refractive index second sub-capping layer 152) exhibit better performance, significantly improving light extraction efficiency and current efficiency, which is beneficial for achieving wide color gamut, low power consumption, and high brightness display products.

[0262] The organic compounds in this application are fluorine-free and have relatively weak intermolecular forces, resulting in stronger adhesion to the electrode or organic material film interface and more stable interlayer stacking after film formation. Furthermore, the amide, aromatic, and heteroaromatic groups in the organic compounds of this application can introduce certain conjugated characteristics, possessing higher excited-state energy levels, not affecting the color of visible light, and exhibiting high thermal stability, making them high-performance low-refractive-index capping layer materials.

[0263] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0264] The embodiments described above are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. An organic compound, characterized in that, The chemical structural formula of the organic compound is shown in general formula (1): （1）； in, Z is selected from -CR5 or nitrogen atom, and multiple Z in general formula (1) are selected from the same or different groups; X1 and X2 are each independently selected from at least one of the following: single bond, double bond, oxygen atom, sulfur atom, -NR6, -CR7R8-; X3 is selected from single bonds, double bonds, oxygen atoms, sulfur atoms, -NR6, -CR7R8-, and -CR9-CR. 10 -、-CR 11 =CR 12 At least one of them; R1, R2, R3, R4 and R5 are each independently selected from at least one of hydrogen, a straight-chain alkyl group having 1 to 16 carbon atoms, a branched alkyl group having 1 to 16 carbon atoms, a straight-chain alkoxy group having 1 to 16 carbon atoms, a cyclic alkyl group having 3 to 30 carbon atoms, an aromatic group having 6 to 30 substituted or unsubstituted cyclic atoms, and a heteroaromatic group having 5 to 30 substituted or unsubstituted cyclic atoms. R6, R7, R8, R9, R 10 R 11 and R 12 Each is independently selected from at least one of hydrogen, methyl, substituted or unsubstituted phenyl; a, b, and c are each independently selected from 0 or 1, and a and b are not both 0 at the same time; m and n are each independently selected from 1, 2, 3, 4 or 5.

2. The organic compound according to claim 1, characterized in that, Z, X1, X2, X3, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 and R 12 None of them contain fluorine atoms.

3. The organic compound according to claim 1, characterized in that, The organic compound is selected from any one of formulas (2-1), (2-2), (2-3), (2-4), and (2-5): 。 4. The organic compound according to any one of claims 1-3, characterized in that, R1, R2 and R5 are each independently selected from at least one of hydrogen, methyl, isopropyl, tert-butyl, adamantane, substituted or unsubstituted phenyl, biphenyl, 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthalene, 2,2-diphenylpropane, tetraphenylmethane, tetraphenylsilane, 9,9-dimethylfluorene, 9-methyl-9-phenylfluorene, and 9,9-diphenylfluorene; R3 and R4 are each independently selected from at least one of hydrogen, methyl, and phenyl.

5. The organic compound according to claim 1, characterized in that, The organic compound is selected from any one of the following compounds: 。 6. A mixture, characterized in that, The mixture includes at least one organic functional material and at least one organic compound as described in any one of claims 1 to 5, wherein the organic functional material is selected from at least one of hole injection materials, hole transport materials, electron injection materials, electron transport materials, light-emitting auxiliary materials, hole blocking materials, guest materials, host materials, capping materials, and quantum dot materials.

7. A composition, characterized in that, The composition comprises at least one organic solvent and at least one organic compound as claimed in any one of claims 1 to 5, or the composition comprises at least one of the organic solvents and a mixture as claimed in claim 6.

8. An organic light-emitting device, characterized in that, The organic light-emitting device includes: First electrode; A light-emitting functional layer is disposed on the first electrode; The second electrode is disposed on the side of the light-emitting functional layer away from the first electrode; and A cover layer is disposed on the side of the second electrode away from the light-emitting functional layer; The material of the covering layer includes at least one organic compound as described in any one of claims 1 to 5, or the material of the covering layer includes a mixture as described in claim 6, or the covering layer is made of a composition as described in claim 7.

9. The organic light-emitting device according to claim 8, characterized in that, The cover layer includes a first sub-cover layer and a second sub-cover layer, wherein the second sub-cover layer is located on the side of the first sub-cover layer away from the second electrode; The material of the first sub-coating layer includes at least one of the organic compounds, and the refractive index of the first sub-coating layer is less than the refractive index of the second sub-coating layer.

10. A display device, characterized in that, The display device includes the organic light-emitting device as described in claim 8 or 9.

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